Socket is Mac and there is more than one number on it. When I went to the Mac web site none of the numbers came up using their search function, what is stamped is (I think) PN SC130, also E2, and a small 01. Best bet would be SC130, the others may be date of manufacture and maybe the plant?

Someplace in the garage is an old mac catalog I'll take a gander in there and report back.

Edit:
From a 1990 Mac catalog it's PN SC130 "Eaton Tamper-Proof Socket" for a #2 Eaton, price back then was $7.15 (now it's probably $27.15).

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Last edited by 383S_Fastback; 06/23/09 08:04 PM.
'67 & '68 Barracuda FB's
'70 AAR Cuda
'89 Ramcharger 4x4
'06 Ram 2500 CTD 6 spd

...Mopars are always way out back
Between the muddy river and the rusty railroad track
Yeah, the Mopars are always hard to find
But you can always find a few
There’s Cordobas and Furys and Darts and Dusters too
There’s a Diplomat with a Swinger
A new Yorker a Demon and a Scamp
And there’s a 68 Barracuda grill with both headlamps...Slaid Cleaves - Skunk Juice